A centrifugal barrel polishing machine includes one or more barrels which are rotated in a planetary manner and into which are put workpieces and abrasive media (water, compounds and the like are added if necessary). The workpieces are abraded by the abrasive media in a manner of relative movement difference between the workpieces and the abrasive media resulting from a centrifugal force. Active research has been conducted on improvement in a work polishing amount per unit time (polishing speed) in a polishing machine using the centrifugal force. Patent Document 1 discloses a technique of increasing a polishing amount from the point of structural parameter.
Symbol “R” designates a revolution radius of a barrel. Symbol “r” designates a radius of the barrel. Symbol “N” designates a revolution speed of the barrel per second. Symbol “n” designates a rotation speed of the barrel per second. Patent Document 1 discloses that a polishing amount is increased and a time required for the polishing is shortened when a ratio of a rotation speed to a revolution speed (n/N) is set to about −3.4≦n/N≦−1 under the condition that a ratio of a revolution radius to a rotation radius (R/r) is ranged as 1.5≦R/r≦8.
Patent Document 1 further discloses that the structure is simple and the manufacturing cost can be reduced when n/N=−1 and that this case is preferable as compared a case where −1<n/N<0 in which the structure is complicated and the efficiency is low. The effects disclosed by Patent Document 1 are actually accepted widely. Many of generally manufactured centrifugal barrel polishing machines have been designed on the basis of n/N=−1 for about 40 years since Patent Document 1 was published.